CHAPTER 2: LITERATURE REVIEW
This chapter will discuss the previous literature about the increasing number of elderly in the world and Malaysia, their health status and previous study about the Kettle Test to evaluate their cognitive skills in older people.
2.2 Older people in the world and Malaysia
The number of elderly people is continuing increase around the world in recent years as the rates of fertility have decreased to very low levels across the world. It is predicted that there will be a higher percentage of an elderly in some countries. According to a recent report by He, Goodkind, and Kowal (2016) in An Aging World: 2015 International Population Reports, they stated the older people aged 65 and above is 562 million or 8.0 per cent when the worldwide population reached 7 billion in 2012. 3 years later in 2015, the ageing population increase to 55 million and the percentage of this population reached 8.5 per cent of the total population. In 2017, the people aged 60 or over is estimated at 962 million or 13 per cent of the global population (United Nations Department of Economic and Social Affairs, 2017). Malaysia is also no exception in this ageing population trends. According to the Department of Statistics Malaysia (2015), there is 2.83 million or 9.13 per cent of an elderly from Malaysia’s total population which is 21 million. The numbers of an elderly in Malaysia is growing to 3.9% since 2000 and in 2025 this population is expected to grow to 8.7 per cent and more worst to 16.3 per cent in 2050 (United Nations, 2009).
2.3 Physiological, psychological, and psychosocial status among older people in Malaysia
Ageing, which could not be avoided and processes with complex, multifactorial, is characterized by progressive deterioration of the system of organs and tissues (Nigam, Knight, Bhattacharya, ; Bayer, 2012). An elderly may deal with many health complications as they are getting older. They faced multiple issues in the physical, psychological and psychosocial aspect that can affect their daily living. According to Ocampo-Chaparro et al. (2013), the physical health, mental and social activities gradually decrease and can cause the status of the function may be affected due to a limitation in daily life activity. In the same way, changes in health status that occur due to ageing are more chronic than acute and more progressive than regressive. There are much common health problems that elderly need to face such as eye vision, neurological disorder, joint pains, heart complications, asthma, skin disease, urinary problems, tuberculosis and other (Balamurugan, 2012). Besides that, an elderly also suffer from mental health problems such as loneliness, depression or isolation. Valtorta and Hanratty (2012) state that based on community studies, the percentage of adults aged 65 years old and above that have severe loneliness is from between 2% and 17% and individuals over the age of 55 feel lonely at any one given time up to 32%. The other common health problems for elders is a cognitive impairment including mild cognitive impairment and variety types of dementia that related with increased risk of disability and death. The prevalence of cognitive impairment is estimated higher than 40 per cent among elderly people aged 80 years and above (Ren et al., 2018). Cognitive impairment is burdensome and can affect many everyday activities in older people. Thus, it is in tradition that occupational therapist evaluates the cognitive function and the consequences of cognitive impairment daily life activity performance in dementia care to evaluate the capability of person doing, provide interventions to enhance engagement in daily life of person, and advise the decisions about the proper in managing life (Baum ; Katz, 2010).
2.5 Kettle Test as a screening tool to detect cognitive impairment in elderly
With the increasing rates of cognitive impairment in Malaysia, it becomes one of this study aims to translate and validate the Kettle Test for Malaysian populations. This is because the early detection of cognitive disability would enable health service provider to provide earlier treatment and more effective (Kim et al., 2017). Kettle test is a functional-based assessment for cognitive skills of elderly. It was developed by Adina Hartman-Maeir, Nira Armon and Noomi Katz in 2005 and validated by Adina Hartman-Maeir, Hagit Harel, Noomi Katz in 2009. According to a study by Hartman-Maeir, Harel, and Katz (2009) describe the Kettle Test as a short, top-down measure, cognitive-functional that evaluates the actual performance on IADL’S familiar tasks with integral complexity which can be conducted in clinical or at home setting. The purpose of the test is to assess the ability for CVA’s client who was identified or suspected cognitive impairment that lives independently in the community prior to the stroke. This test can evaluate basic and higher-level of cognitive function such as sequencing and executive function in a functional context by preparing 2 different hot drink with an electric kettle. It is a basic task that was selected due to the importance of its function, have broad cultural relevance and more practical on the requirement of time and tools used in the assessment in several settings. This assessment is a structured observation in which the observer rates the performance of elderly on 13 separate steps to complete the task. The guideline to give cues is given so that the assessor scores every step based on the cueing’s degree that needed to complete the step. The higher the score indicate more assistance which the total score range from 0 to 52.
Hartman-Maeir et al. (2009) states the initial research conduct by A. Hartman-Maeir, Armon, & Katz (2005) that test on 41 elderly clients that suspected of cognitive disability which referred to a geriatric assessment clinic to examine the ecological and convergent validity found there is small to moderate significant correlation in this test with conventional assessment of cognition which is Clock Drawing Test (CDT), Mini-Mental Status Evaluation (MMSE) and Star Cancellation subtest of the Behavioral Inattention Test (BIT). They also found there are moderate correlations with caregiver ratings of ADL and IADLs.
Later in 2009, Hartman-Maeir, Hagit Harel, Noomi Katz conduct a new study to examine the more about the validity and reliability of the Kettle Test in a population of geriatric stroke which dealing with same concern about cognitive deficit’s effects on abilities of daily living when discharge from rehabilitation. According to research conduct by Hartman-Maeir et al. (2009), the researcher found that this test has high inter-rater reliability in a study of ABI patient between four occupational therapists across two sites. The convergent validity of Kettle Test was also studied by comparing this assessment to another frequently used measure of cognitive functional ability in 36 individuals with CVA and 36 healthy control. The correlation between the Kettle Test and the cognitive scale of functional independence measure was excellent. The test also was discovered to moderately correlated with a conventional cognitive measure such as CDT and MMSE. The performance of post-stroke CVA also was not related to their educational background or motor status with no significant difference was found in the study. Thus, this assessment is easy and short time to administer that grants a valid evaluation for clinical practice which may identify cognitive disability in daily life functional activities for those with CVA. The Kettle Test has the shortest administration time which is less than 20 minutes and requires only a few types of equipment in term utility of clinical (Poulin, Korner-Bitensky, ; Dawson, 2013).
Another study had been done by Wall, Cumming, and Copland (2017) to explore the association between cognitive performance test and comprehension’s performance and naming tests in stroke survivor aphasia. They also study the relationship between the real-life measure of cognition which is Kettle Test and the language performance and explored the practicability of administration in this tests to aphasia patients. This study was conducted to 36 post-stroke aphasia participants and 32 healthy controls were test using pen-and-paper neuropsychological tests such as Star Cancellation, The Brixton Spatial Anticipation Test, Trail Making Test (Parts A and B), and Kettle Test for stroke. They also used a Comprehensive Aphasia Test to evaluate the auditory comprehension and Boston Naming Test to measured naming. 22 community-dwelling participants who have aphasia were asked to do the Kettle Test. They used multiple linear regressions to investigate the association between language performance and cognitive test’s performance. The quantifying missing data was used to find out the feasibility. Their result showed that the cognitive test with the highest variance is accounted for based on an understanding of auditory and naming using Animal Fluency task and Hopkins Verbal Learning Test. The cognitive tests were significantly associated with naming task and auditory comprehension, but the Kettle Test and Start Cancellation Test are not associated. This study confirmed that the everyday real-life measure of cognitive not significantly associated with an auditory comprehension and naming in aphasia. Thus, The Star Cancellation Test and the Kettle Test can be used to post-stroke aphasia but need to be tailored to make improve their understanding of the tasks to make more practical and maximize the accuracy to test to them.